Quenching in the nitrogen system has also been the subject of many studies over the years
[1]}, [2]}, [3]}, [4]}, [5]}, [6]}, [7]}, [8]}, [9]}.
As with methane, the underabundance of ammonia in brown dwarfs cold
enough to favor it has been attributed to disequilibrium chemistry [6]}.
The visibility of ammonia has been made the distinguishing characteristic of the Y dwarf,
the newest, coldest, and possibly last member of the stellar spectral
sequence [11]}.
The NH\(_3\) -N\(_2\) -HCN system differs from CO and CH\(_4\)  in interesting ways
that lead to significantly different behavior.
